The present invention refers to a semirigid locking system for a firearm of a type having a breech block which travels between a locked position in which the breech is fixed to the stock and a release position in which the breech is disengaged from the stock through actuation of a spring-loaded control member which is received within the breech.
Austrian Pat. No. 382 760 discloses a locking system of this type in which the breech has at least one bore for supporting a radially movable locking element which is in registration with an engagement surface of the stock in locked position of the breech while being supported by the control member, and is disengaged from the engagement surface in release position of the breech block through displacement of the control member in parallel relationship to the breech.
A drawback of this conventional locking system is its rigid configuration, with locking elements being formed as toroidal segment and in registry in locked position of the breech block with the engagement surface in form of an annular groove. The disengagement of the breech block is effected by a separate gas control system. In a locking system of this type, the locking elements are subject to a shearing action between the stock and the breech block which is commensurate with the total energy of the cartridge. The annular groove adversely effects the stability and the oscillation behavior of the stock. Moreover, as a result of the unattenuated cartridge power, this type of locking system does not permit the use of light metals or plastic material as increasingly demanded to date.